The long-period comet C/2000~WM1 (LINEAR) was exceptionally
bright at the time of its discovery in November 2000 at a
heliocentric distance of ~6~AU. Although its
performance near perihelion fell short of expectations, the
comet was still an excellent target because it passed within
0.3~AU of the Earth in December 2001. During that time we
organized a campaign of ultraviolet observations using both
the Hubble Space Telescope (HST) and the Far
Ultraviolet Spectroscopic Explorer (FUSE) and obtained
spectra covering a wavelength range from 910-3566~Å. The
spatial brightness distributions of OH and CS were measured
using the HST data. Emissions in the CO Fourth
Positive Group near 1500~Å\ were marginally detected in
the HST spectra, but emissions from S2 and the CO
Cameron system are apparently absent. Over 90 emission
features were detected in the FUSE spectra, including
the C-X, B-X, and E-X bands of CO, at
least 3 lines of H2, a multiplet of N~I, several
multiplets of O~I and C~I, 10 members of the H~I Lyman
series, and possibly emission from O~VI. However, most of
the lines remain unidentified. The estimated CO abundance
was only ~0.4%, which is among the smallest value ever
measured. We searched for, but did not detect, argon in the
FUSE spectra and estimate that [Ar/O] is depleted by
at least a factor of 13 relative to the solar value. The low
CO abundance and the absence of S2 and argon implies
that the nucleus of C/2000~WM1 (LINEAR) has been warmed to
\geq60~K for a substantial period of time, which suggests
a formation region at a relatively small heliocentric
distance.